Safety friction-clutch.



Patented. Se t; 21', 19ml 1 I. D. WILLIAMSON, JR.

' SAFETY FRICTION CLUTCH.

I V APPLICATION 111.21) mums, 1910. v 971,335.

fJi n. WILLIAMSON, J11.

SAFETY FRICTION CLUTCH. 7 APPLICATION TILED alums. 1910.

Patented Spt 27, 19101 T 2 SKEETS8HEBT 2.

To all whom it may concern: i

Juan 1). WILLIAMSONL 311., or PHILADELPHIA, PENNSYLVANIA, nsston'on T WILLIAMSON BROS. (10., 0F PHILADELPHIA,'PENNSYLVANIA, A CORPORATION OF PENNSYLVANIA.

Apglicationiiled January 25, 1910. Serial no. 539,921."

Be it known that I, Jonn I). ll lnLmmson, .lr., a citizen of the United States, residing in Philadelphia, Pennsylvania, have invented certain improvements in Safety Friction- "(Jlutchcs, of which the following is a specitieation. v

One obJect of my invention is to provide a t .utch for coupling a driving to a driven number, which shall transmit. a predeterit: ned torquet'roni one of said members to is other, but -which when this torque is exceedethwill automatically actto permit or. cause the driven inember'to slip relatively to the driving member.

Another object. of the invention is to pro vide a novel form of automatically acting friction clutch so designed to antoinatically limit the torque transmitted between the driving and driven members, between L which it is coupled.

These objects and other advantageous ends; I secure as hereinafter set. forth, reference being bad to the accompanying drawings, in which v v v I Figure 1, isa vertical section illustrating the detail cons ruction of a clutch constructed according to my invention; Fig. 2, is a vertical section on the line (z (1, Fig. 1; Fig. 3, is an end elevation of the clutch; Figs. 4- and flare perspective views on a reduced Scale illustrating the construction of certain parts of'my device; Fig. 6, is a fragn'lcntary plan illustrating the construction of the spring ease and its associated parts; Figs. 7 and sore respectively a sid! and an and elevation of a modified form of my invention, and Fig. 9, is a fragmentary plan illustrating: one of the detailsof the clutch shown in Figs. 7 and S.

In the above. drawings, 1 represents a gear or other device to which is ordinarily connected the load to be driven. and Q represents a shaft loosely supporting said gear and designed to be connected to any suitable source of power. The gear has connected with it, (in the present case. integrally) a disk 3 having on one taco two projecting lugs 4 and 5, in the latter of which is mounted an adjustable bolt or set screw (3 held in any adjusted position by means of a jam nut 7. 2 is a second disk 8, on one of whose faces is mounted a pivot pin 9 which extends 'to- Specification of Letters Patent. Pa 31 (ed Sept Also loosely mounted on the shaft 3 ward the disk 3 and carries a three armed SAFETY FRICTION-GLUTCH..

lever 10. Also mounted on the disk 8 is a short shaft or spindle 11, pl'fljt'tjl'lllg on both faces thereof and harm lined on its end adjacent to the lever 10, an arm 12 con-1 nected to one of the arms of said lever by -a link 13. On the other end of this shaft 11 and on the other face of t'lletlisli S, is

a second arm 14. V I

' The shaft 2 has keyed to it a friction wheel 15 designed to receive a friction hand 16 which-has one of its ends contacted to the arm It and its other end adjustably fixed to :1 lug 1T projecting from the disk 8. This latter has nunnncd between itself and the disk a casing 15 in which is a spring 19 contined betwcrn the lug 1 and the second who.

of the arms of the levcr the third arm of said lever extending so as to be capable of being engaged by the end of the bolt (3 under certain conditions of operation, If the shaft EZ-a'nd wheel be turned in the direction of the arrow, Fig. 3, power is a transmitted to the band 16, lug 17, disk 8 j and stud. J to one arm 10 of the lever 10..

The pressure against this lever arm causes said lever to turn on said stud and through V friction wheel 15. The power forklriring the load is thus transmitted from thc'lerer 10 tospring, 1'9.- lllfl 4, and disk ,3 to the gear '1. its the load transmitted from the shaft 2 re said gear is increased, the spring 19 1S compressed to an amount depending on said load, and the'lever' 1U further turned on its pivot, thereby rausiug'the friction band 16 to more tightly grip the friction wheel 15. so that it is enabled to transmit such increased load without slipping Thereafter. it the load applied to the gear be increased, the friction band 16 will slip on the wheel 15, since the holtwill cause said band. As soon, however, as the torque transmitted from the driving to the drlven such a turning of the lever 10 as will slack w uumuiionmummmh; "a.

30 and projecting substantially parallel with Q q r 971,335

7 member falls to the predetermined point,

the friction band ceases to slip and the load is transmitted as before. If the load to be transmitted is larger than it is desired tocarry through the spring 19, I may place air-- other lug 30 on the disk- 3 and :1 corresponding lug 31 on the disk 8 atthe same time mounting a spring 32 of the proper dimendriving mechanism.

sions between said two lugs. In this case the spring 32 serves to transmit the major portion of the load while the controlling 5 ring 19 is so proportioned'as to yieldsulticiently at the predetermined additional load to cause operation of the lever 10, as above described. Itis obvious that an desired number of springs 32 may be us to satisfactorily transmit the main part of any desired load, or they maybe omitted altogether when the spring 19 is sufiicient for this purpose. By varying the position of the bolt 6, it is possible for the device to be set so that it will slip at any desired load within the limits for which it is designed, thereby preventing possible injury to the apparatus to which it transmits power, or to any of the In that formof my-in vention shown in Figs. 7 to 9 inclusive, I have simplified the constructioi-i by providing the disk 3 with an arm 3 mounted adjacent to its periphery the shaft 2 over to the friction band wheel 15. In addition I mount on the disk 8, a lever 10" in such a position that it also extends sui'istantiully parallel to the shaft 2 and is held in position by a radially placed fulcrum bolt 9. tlne end of this lever 10 is connected to one end of the friction band 16, whose other end as before is connected to :1 lug 17 on the dislt The second end of the lever projects between the two disks 3 and 8 and has mounted between it and the I arm 3" the spring 19. preferably though not Iadjustable almtmentti so mounted and proportioned as to bev capable of engaging the friction band end ofthc lever 10 under predetermined conditions. 7 i

\lfith the above described arrangement of parts, the load, as before, is designed to be applied to the disk 3, and for this purpose the pinion 1 is directly engaged by the.

driven member. The source. of, iower is connected to the shaft 2 and und ating conditions it is obvious that the turning of the wheel 15 causes pressure to be exerted through the band 16, lug 17, disk 8 and fulcruin'pin 9 upon the lever 10. One arm (if/said lever is thus caused to press agains the sprin 19, thereby transmitting the power throng i it to the disk 3and gear er' opcr t 1. The compression of the spring causes the lever to turn upon its fuh-ru'mpin 9" so as to. t ghten the friction band ltlupon the friction wheel 15, thereby makin said band viously adjusted abutment formed by the set screw 6. 'lhcrca'fter any further increase friction wheel 15 to slip relatively to the band 16, since this latter cannot be firther of said band.

I claizn'. 1 j L 1. 'lhe combination in a power transmither; a friction band operative on one member; and means for automatically tightening said band in proportion to the load applied.

2. The combination in a power transmitting clutch of a driving and a driven member; a friction band operative on one member; and means for tightening said band in proportion to the load applied; with means for limiting the possible amount of tightening of said band.

3. The combination in apower transmitting clutch of a driving and a driven member; a friction band operative on one of said band to the other member; said means including a lever having one arm operatively connected to said band and a second arm in position to be acted on by said second member. t

'4. The combination in a power transmitting clutch of a driving and a driven member; a friction baud operative on one of said members; means for connecting said band to the second member; the same including a lever having one arm operatively connected to said band and. a second arm in position to be acted on by said second ble turning of said lever.

The combination in a ower transmit her; a level mounted on one of said memmcinbrr; means for operatively connecting the lover to the friction hand; and a second structure on the first member capable of acting on said lever, for limiting the movement thereof.

6. The combination in a ower transmithund operative thereon; a structure to which one end of the friction band is attached; a

rip the wheel as before described. As the i tightened, by reason of the action .of the set screw 6, which acts to cause, a slacking off ting clutch of a driving and a driven memmembers; with means for; connecting said member: with means for limiting the possi-.

ting clutch of a driving and a driven mom-- 16 comes into engagement with the pre in'the load applied to the gear 1 causes the brrs; a friction band operative on the second 1 ting clutch of a friction w cel; a friction shaft mounted in said structure having an arm connected to thesecond end of said band; a lever havin" one arm erativel b connected .to said shaft; with a niember connected to a source of power and operative upon a second arm of said lev'er to transmit power thereto.

7. The combination 111 a power transnatting clutch of a friction wheel; a friction hand operative thereon; a structure to which one end of the friction band is attached; a

shaft mounted in said structure and having;

an arm connected to the second end of said band; a lever having t.

connected to said sha with a member conneczed to a source. ofpower and operative upon a second arm of said lever to transmit power thereto; said member also having means for limiting the movement of the lever when power is applied thereto.v

lever having one of its arms connected to said friction element; and a-second member having a portion engaging one of the arms of the lever to transmit power thereto, and also provided with an adjustable bolt for limiting the. amount of movement of. the

lever. 4'

10. The combination of a member havin two projecting lugs; a shaftsupporting sair member; a friction wheel fixed to said shaft; :1 disk loose on the shaft; 2. spindle carried by said arms-on said spindle; a friction one arm operatively band. having onee'nd connected to the disk:

and the other end connected to one of the arms on the spindle; a lever mounted on the disk having one of its arms connected to a second arm on the spindle; a spring between one of the lugs ofsaid member and'a second arm of the lever; and a bolt mounted in the second lug on the memberso as to engage a third arm, of the'lever. 1 11. Thecombination in a power transmitting clutch of a driving and a driven ymember; means including a controlling spring for limiting the torque tr'ansmitte between said members; and a load transmit ting spring also connected between the members. a 12. The combination in a power transmitting clntch of a driving and a driven member; a friction wheel connected to one of the members; a friction band operative thereon;

means including a controlling spring 0on nected between the friction band and the" second of the members for limiting the load transmitted by said 1 band; and a power transmitting spring also coimectcd between the band and the second member.

13. The combination in a power transmitting clutch of two disks; a friction wheel; a

friction band operative onsaid wheel and connected to one of the disks; a lever mount-- ed on Silld latter disk and connected to one end of the friction; band; a controlling spring. mounted between said lever and the other disk; and a power transmitting spring mounted between the two disks. y

In testimony whereof, I have signed my name to this specificationgin the presence ofso two subscribing witnesses;

, JOHN 1). WILLIAMSON, JR.

lVitnesses fuming E. BRADLEY, lVrr. A. BARR. 

